[jira] [Created] (ARROW-10676) [Python] pickle error occurs when using pyarrow._plasma.PlasmaClient with multiprocess on mac (python3.8.5)

["BinbinLiang (Jira)" <ji...@apache.org>]

BinbinLiang created ARROW-10676:
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             Summary: [Python] pickle error occurs when using pyarrow._plasma.PlasmaClient with multiprocess on mac (python3.8.5)
                 Key: ARROW-10676
                 URL: https://issues.apache.org/jira/browse/ARROW-10676
             Project: Apache Arrow
          Issue Type: Bug
          Components: Python
    Affects Versions: 2.0.0, 0.17.1
         Environment: OS: mac os catalina 10.15.6;
Python version: python3.8.5;
            Reporter: BinbinLiang


* The environment is：
 ** OS: mac os catalina 10.15.6;
 ** {color:#FF0000}Python version: python3.8.5;{color}
 * {color:#ff0000}It's ok, when use python3.7(3.7.2 or 3.7.3) or python3.6(3.6.8).
The error occurs only in python3.8.5.{color}
 * When I use 'pyarrow._plasma.PlasmaClient' in the 'multiprocessing.context.Process', the error occurs.

 ** First, I have a subclass of 'multiprocessing.context.Process', named Executor;
The defined code like this: 'class Executor(Process):' .
 ** And then, I create a 'PlasmaClient' object in the '__init__' function of 'class Executor' .
 ** Finally, I new a 'Executor' object, and call the 'start()' function. 
 * The detail informations of traceback are as follows:
 Traceback (most recent call last):
 File "/Users/liangbinbin/PycharmProjects/waimai_data_cubeinsight/python/taf/server/taf_server.py", line 100, in LaunchExecutor
 executor.start()
 File "/Users/liangbinbin/Applications/anaconda3/envs/python3_8/lib/python3.8/multiprocessing/process.py", line 121, in start
 self._popen = self._Popen(self)
 File "/Users/liangbinbin/Applications/anaconda3/envs/python3_8/lib/python3.8/multiprocessing/context.py", line 224, in _Popen
 return _default_context.get_context().Process._Popen(process_obj)
 File "/Users/liangbinbin/Applications/anaconda3/envs/python3_8/lib/python3.8/multiprocessing/context.py", line 284, in _Popen
 return Popen(process_obj)
 File "/Users/liangbinbin/Applications/anaconda3/envs/python3_8/lib/python3.8/multiprocessing/popen_spawn_posix.py", line 32, in __init__
 super().__init__(process_obj)
 File "/Users/liangbinbin/Applications/anaconda3/envs/python3_8/lib/python3.8/multiprocessing/popen_fork.py", line 19, in __init__
 self._launch(process_obj)
 File "/Users/liangbinbin/Applications/anaconda3/envs/python3_8/lib/python3.8/multiprocessing/popen_spawn_posix.py", line 47, in _launch
 reduction.dump(process_obj, fp)
 File {color:#FF0000}"/Users/liangbinbin/Applications/anaconda3/envs/python3_8/lib/python3.8/multiprocessing/reduction.py", line 60, in dump{color}
 {color:#FF0000}ForkingPickler(file, protocol).dump(obj){color}
 {color:#FF0000}File "stringsource", line 2, in *pyarrow._plasma.PlasmaClient.__reduce_cython__*{color}
 TypeError: no default __reduce__ due to non-trivial __cinit__



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